Differential torque equalizer



May 15, 1962 E. J. MILLER DIFFERENTIAL TORQUE EQUALIZER 3 Sheets-Sheet 1 Filed May 5, 1960 INVENTOR. 506505 J M/Zl W y 1962 E. J. MILLER 3,034,322

DIFFERENTIAL TORQUE EQUALIZER Filed May 5, 1960 3 Sheets-Sheet 2 Y 1952 E. J. MILLER 3,034,322

DIFFERENTIAL TORQUE EQUALIZER Filed May 5, 1960 3 Sheets-Sheet 3 3,034,322. DIFFERENTIAL TORQUE EQUALEZER Eugene J. Miiier, 411 Gilli Ave, McHem-y, ill. Filed May 5, 1960, Ser. No. 26,289 2 Claims. (Ci. 64-26) ment with the ground; and the resulting motion of the" wheel which has lost is traction engagement is transmitted back to the other wheel through a hydraulically driven torque equalizer.

One of the objects of the invention is the provision of such a differential torque equalizer for the opposite wheels of differentially driven vehicles which permits the flexibility and differential of speed that is necessary for such difierentially driven wheels to turn corners.

Another object of the invention is the provision of such a differential torque'equalizer which is simple in construction, which has a minimum number of parts, which is adapted to be manufactured economically, and which does not depend for its action on the application of a brake, but which is automatic in transmitting the motion of a wheel or shaft which tends to slip back to the other shaft of the differential, and thus tends to equalize the traction.

Another object of the invention is the provision of such c aaaaazz Patented May 15, 1952 and 15 are indicated at 58 and 59; and the ring gear 57 is rotatably mounted on the shaft 11. Shaft 11 has a driven gear of the bevel type, indicated at 60, keyed to the shaft; and the shaft 15 has a bevel gear 61 keyed to the shaft.

Between the ends of the shaft members 11 and 15 there is mounted a spider 62, which has a plurality of bevel a differential torque equalizer which utilizes a hydraulical- 1y driven connection between'the two driven shafts of a I differential that can be enclosed in the same differential housing, and which utilizes the saineoil or lubricant that is used for lubricating the differential, and .in-which the characteristics of the hydraulic drive may be adjusted to 1 oils of different viscosity.

Another object of the invention. is the provision of a plurality of differential torque equalizers which prevent either driven shaft from slipping without transmitting force back to the other shaft.

Another object of the invention is the provision of a plurality of different arrangementsfor differential drives Other objects and advantages of the invention will be apparent from the following description and the accompanying drawings, in which similar characters of reference indicate similar parts throughout the several views.

Referring to the drawings, of which there are three sheets,

FIG. 1 is a diagrammatic assembly drawing of a differential torque equalizer embodying the invention;

FIG. 2 is a side elevational view of the moving parts of the hydraulic equalizer;

FIG. 3 is a fragmentary sectional view taken on the plane of the line 3-3 of FIG. 2;

FIG. 4 is a similar view of a modification including a hydraulic torque equalizer.

Referring to FIG. 1, indicates the differential housing provided with semi-solid lubricant and having the usual filling plug (not shown) and drain plug 51. The differential housing 50 has laterally extending tubular portions 52, 53 provided with ball bearings for rotatably supporting the shaft members 11 and 15.

The differential housing 50 has a forwardly extending tubular portion 54 provided with a suitable ball bearing for supporting the drive shaft, having a driving gear 56, which is driven by the engine, and which drives a ring gear 57.

Roller bearings for supporting the shaft members 11 around the ring gear '57.

gears 63, 64 mounted thereon for engaging the bevel gears 59 and 602 One of the bevel gears 63, 64 is driven by the ring'gear 57.

So far the differential may correspond to any conveni tional differential gear system in which the drive shaft 54 driven at different speeds, the spider 62 with its bevel.

gears 63, 64 rotates and the bevel gears 63, 64 travel suitable driving traction and the other slips, :then the power may be lost entirely at the slipping wheel; and it is the object of the present inventionto equalize the torque onboth axles to avoid such slipping.

The differential housing 50 is provided with auxiliary bearings 16 on its lower inner wall for-rotatably supporting a pair of auxiliary shafts 17 and 1%. The shaft 17 has pinion 13; and shaft 18 has pinion 12 keyed thereto.

Pinion 12 meshes with gear 10 keyed to shaft 11; and pinion 13 meshes with gear 14 keyed to shaft 15.

Shaft 18 has a housing 25 secured to the end of the shaft and provided side plates 26, Hand a peripheral wall 28, forming a hydraulic pump housing. A shaft extension 171: extends into the housing walls 26, 27 and is connected to shaft 17 by a flexible coupling 30.

One form of hydraulic pump which may be employed in the present device is the gear type, further details of which are shown in FIGS. 2 and 3. In: such case the side plates 26 and 27 have bearings 31 and SZrotatably supporting shaft 33 and bearings 34, 35 rotatably supporting shaft 36.

A central pumping gear 37 is keyed at 38 to the shaft 170, which is held in the pump by an-annular rib 39 engaged in an annular groove '40 in a plate 41 secured to side plate 26. Gear 37 meshes at 42 with gear 43 rotatably mounted on shaft 33 and also meshes at 44 with gear 45 rotatably mounted on shaft 36. Referring to FIG. 2, the peripheral wall or middle plate 28 of the pump between the side plates 26 and 27 is formed with cylindrical bore 46 for housing the central gear37; and bore 46 communicates with the parallel cylindrical bores 48 and 49 for the other gears 43 and 45.

The middle plate 28 of the pump is secured between the side plates by a plurality of through bolts 70; and the middle plate of the pump is provided with tapering inlet openings 71, 72, 73, 74; and the inlet openings 71, 72 lead to the gear '43, while inlet openings 73,74

lead to the gear 45.

The central plate 28 of the pump is provided with out- If one traction wheel has a upon the rotation of the shafts ligand and when the traction is equal on both wheels, shafts 11 and 15 rotate at the same speed; and the same is true of the shafts 17 and 18, which cause the pump housing to rotate, and gears 43, 37, rotate withoutany pumping action.

The tapered openings 7174 in the peripheral Wall 28 of the pump constantly scoop in a supply of lubricant at one side or the other, depending on the direction in which the-housing 25 is rotating, so that the gears are supplied with lubricant by this scooping action and by the fact that the pump islocated in the lowest part ofthe oil filled differential housing.

When one wheel slips on the vehicle. so that there isfa I tendency. for one shaft 11' to rotate faster than the other shaft 15, the faster rotation of shaft 11 is'transmi-tted by gear- 10 to pinion 12 and shaft 18, which rotates the housing'ZS relative to the pump gears and causes'the gears to pump oil on one side or the other. 1 v The flow of this oil is restricted at one or" the outlet ports 75-78 by the restriction plugs 83; and torque is transmitted from shaft 18 to shaft 17 through the hydraulic pump. 7 p

Thus the tendency of the slipping wheel to slip is re strained; and the torque is equalized between the shafts 11 an'd'15.

, -.Referring to FIG. 4, this is a view-similar; to FIG. 1 50f a modification having a hydraulic drive unit 1150 connected to the driven shafts to equalize the torque and prevent slipping of either wheel.

suitable bearings (not shown). 7

The differential housing .103 is provided with the roller bearings 104 and 105 forthe shafts102, 101, which carry the gears 106, 107. The driving shaft is indicated at 108,

whereit is mounted'in ball bearings 1G9, 110 in a housing, extension 111.; The driving shaft 108 carries the ing-114.

Between the vanes there is a rotor 142 carried by the end of shaft 124 and having similar vanes 143 between the vanes 139 and 140; and the chamber is filled with semi-solid lubricant or liquid lubricant, which produces a hydraulic connection between the vanes on shaft 123 and the varies on shaft 124.

The shaft 124 extends into the gear housing 137, where it fixedly supports a gear 14% meshing with a pair of gears 145, 146. Gears 145, 146 are mounted onstub shafts147, 143 carried by universal cross head 149, which is flexibly mounted on. shaft 150 by means o-f'plate 1S1.

Shaft 150 is indriving connection drivenshaft1012 through gears 1%, 129,139. A seal 152 surrounds shaft 1591M cover 153; and the chambers.137, 138 are also summer lubricant. v

The operation of the hydraulic drive 106} is as follows:

7 When shaft 123 is rotated with'respect to shaft 150, the

vanes in the housing 122 tend to carry with them the lubricant in the chamber 136, which carries with it the vanes 142 on the shaft 124, driving the gear 144, which drives the gears 145, 145, causing the cross head 14910 rotate, and rotating the shaft 15%.

In this modification there are two driven shafts 101 and 1il2 extending to driven wheels (nots'hown) where they are provided driving pinion 112, whichengages with the teeth of the ring gear7113, which is attached to a rotatable hous- The extension housing 111 carries another roller bear-' ing 115 for theend of the driving shaft 108.

The ring gear housing '114 has a pair of stub shafts 116, 117 carrying bevel pinions 118, 119, which mesh' withthe bevel pinions120, 121 carried by the driven shafts 161, 102, respectively. When the driving shaft 168 rotates, po-weris transmitted to both the driven shafts the'power is equally divided between the two shafts; but if one shaft a wheel that slips and the other wheel holds, the bevel gears 118121 will permit one shaft to standstill, while the other rotates freely, were it not for the hydraulic connection between the two shafts 101, 102 -which is provided by the hydraulic drive or torque equalfizer 100.. t l a I Thistorque equalizer preferably comprises a separate housing 122 and a separate pair of aligned shafts 123, 124. The diiferential housing 103 has a pair of additional extensions 125 and 1-26 containing gears 127, 128, 129,

130. Gears 127 and 129 are idler gears mounted on stub shafts 131, 132 in the'housings 125, 126; and they mesh with gears 167 and 166, respectively.

Gear 128is fixedly mounted on shaft 123, which has a 1 bearing'at 133 in the housing extension 125 and another bearing at 134 so that shaft 123 is driven by'the train of 1 gears 107, 127,128.

Theshaft 123 supports'thehousing'122 by'rneans of the attaching flange 135; and housing 122 comprises a cylindrical member which is provided with an oil chamher 136, a gear charnber 137, and auniversal chamber 1 38. The oil chamber 136 has a multiplicity of radial-1y extending vanes 139 spaced from each other; and there are additional vanes 140 carried by the pantition M1 on the other side of the oil chamber136.

101,102 by the ring gear; and when the tnaction is equal,

Thus the driven shafts 101, 102 are connected by the hydraulic drive 106; and if one shaft tends to stand still while the other tends to slip and rotate, this is counteracted by the hydraulic drive 1&0, which transmits torque from the slipping shaft back to the other shaft, tending to equalize the torque between the two driven shafts.

resistance developed in the drive 16% tends to drive the axlelill through the shaft 123 and gear train 128, 127, 107. Also the resistance caused by the drive 160 tends to transmit power through gears 106, 129, 130 to the shaft 192 and back to. the shaft liil through the gears 121, 118, 119, 12th,

' {it will thus be observed that the present device is adapted to prevent the slipping of either sheel due to loss [of traction and due to the fact that the differential in traction is transmitted to theother'shaft, while still turnin'ga-corrierl- While I have illustrated apreferred embodiment of permitting the wheels to rotate at different speeds while my invention, many modifications may be made without. departing from the spirit 'of the invention, and I do notv wish to be limited to the precise details ofcon'struction set forth, but desire to'avail myself ofall changes within the scope of the appendedclaims.

Having thus described my invention, what I claimas shaft between the ends thereofia slip coupling housing mounted in said dilferential housing in position to be immersed in the lubricant, said slip coupling housing being mounted on said shaft, which comprises two sections, one section rotating in said housing and the other section having its end fixedly secured to said shaft to rotate the coupling housing with the shaft, said, coupling housing comprising a pair of end plates, said end plates having bearings for-supporting a pair of idler shafts between the end plates, said first shaft supporting a pumping gear in said slip coupling housing and said idler shafts each supporting'a pumping gear meshing with the first pumping gear and driven thereby, said slip coupling housing including a housing about said three gears and formed with three. intersecting cylindrical chambers for rotatably receiving said gears, said "slip coupling housing being provided with a: pair of diverging' scooping inlets for each of the gears on the idler shaft and with a pair of outlets extending from the space between each pair of gears, the slip coupling being adapted to have either section of its shaft driven from a differential gear shaft to interpose a resistance to the relative rotation between the two shafts of a difierential driving gear and to transmit back from one shaft of a dilferent driving gear shaft to the other differential driving gear shaft.

2. A slip coupling according to claim 1, in which each of the outlets from said slip coupling housing is pro- 5 vided with a threaded bore and with a restricting nozzle resisting the discharge of liquid lubricant from the slip coupling and increasing the resistance to relative rotation between the shaft sections to which it is attached and increasing the tendency to transmit torque from one 10 shaft section to the other.

References Cites! in the file of this patent UNITED STATES PATENTS Fottinger July 19, 1927 Corey July 4, 1933 Chillson Apr. 10, 1951 Power May 30, 1961 FOREIGN PATENTS Austria Apr. 10, 1952 

